The rule prohibits anyone on the Wildwood boardwalk from wearing shorts, swimsuits, pants or skirts more than 3 inches below the waist. Fines start at $25 for a first offense.

The measure also requires people to wear foot protection at all times and shirts between 8 p.m. and 5 a.m.

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Earlier this month, officials in the Jersey Shore town passed a law banning overly saggy pants on the boardwalk, prompted by numerous complaints from longtime visitors about having to see people's rear ends hanging out in public.

Subsequent violations of the law could result in fines as high as $200 and 40 hours of community service.

The trend, known popularly as sagging, originated in the U.S. prison system, where inmates are not allowed to wear belts. It was popularized by hip-hop artists and embraced by youths.

Authorities in suburbs of New Orleans, Chicago, Atlanta, Detroit, Miami and Jacksonville, Fla., are among those who have passed laws banning overly droopy pants.

Bathing suits are already prohibited on the Wildwood boardwalk, unless covered up by other clothing.

City Commissioner Pete Byron said the city is not trying to be the fashion police.

"There's a line that gets crossed between being a fashion statement and being obnoxious," he said. "Families can feel threatened."

The American Civil Liberties Union of New Jersey has declined to take a position on the law, but other ACLU chapters around the country have said such laws are unconstitutional.

Troiano said he hopes no one will have to be cited by police for violating the ordinance. Rather, he said, a well-placed word from an officer should suffice to persuade boardwalk patrons with overly low-slung jeans to hike them up.

Police Chief Steven Long said his officers will respond appropriately when they see violations.

"The ultimate goal is compliance," he said. "We're just trying to make the city a better place to visit."

The mayor said the city isn't going to be out "hunting these kids down."

"We're not going to be out there with a tape measure," he said. "But we know what's right and not right. If we don't make an attempt to clean our town up, who's going to?"